| Oat (Avena sativa L.) has long been considered a healthy source. And an alternative view is to consider oat as a potential source of specific compounds that can be extracted, purified, and marketed as food complement or incorporated into other food products. From the perspective of the human diet, oat should be regarded as a source of a spectrum of active phytochemicals, which may act in various combinations, perhaps synergistically.Nake oat was used as material to separated its components (starch, oat oil andβ-glucan) according to single-factor and orthogonal experimental. Meanwhile, relative properties and function of extracted components were researched.The results were showed as follows:The best seperation technology condition of oat starch were pH value in 11, time in 1.5 hours, the solid-liquid ratio 1:10. The yield of oat starch was 76.8%, and the purity reached 96.4% with the optimal extracting conditions. Compared with potato starch, corn starch and pea starch, oat starch is higher in solubility and distensibility than corn starch and pea starch, is higher in blue value than potato starch and corn starch, but lower in freezing-thawing stability and transparency than potato starch. Those properties were related to the molecule structure.The optimal extracting conditions of oat oil were extraction pressure in 45MPa, extraction temperature in 40℃, carrying solvent was petroleum ether. The yield of oat oil was 6.266﹪with the optimal extracting conditions. The physicochemical properties of oat oil extracted by supercritical CO2 were shown that acid value was 9.8KOHmg/g, iodic value 117.8Ig/100g, sopanificable value 188.7KOHmg/g, unsopanifcable value 1.87%, refractive index 1.4740, melting point 11.5℃, yellow color(35), red color (3.4), no special odor and taste, and had a slight precipitation. The result of analysis by GC-MS was shown that fatty acid constituents of oat oil were myristic, palmitic, stearic, oleic, linoleic, linolenic and eicosenoic acids. The unsaturated fatty acid was accounted for 80.1% of total oil. The ratio of the saturated, unsaturated and polyunsaturated fatty acid was approximately 0.5:1:1. The effects of oat extracts on hydroxyl radical scavenging and activities of oat extracts were shown that the highest scavenging ability was exhibited by sopanificable matter, then unsopanifcable matter, and the oat oil showed the lowest scavenging ability. For the three samples, their scavenging abilities were positively related to their concentration. The antioxidation of oat oil, sopanificable matter and unsopanifcable matter was valued by the ability to inhibit the lard oxidation and the to scavenge·OH.The optimal extracting conditions ofβ-glucan were temperature in 50℃, time in 3 hours, pH value in 11 and the solid-liquid ratio 1:20. The yield of oat oil was 2.77﹪with the optimal extracting conditions. The rheological property ofβ-glucan had the remarkable relation with concentration ofβ-glucan and the temperature. The viscosity ofβ-glucan remarkably increased with concentration ofβ-glucan in 0.4%-0.5%, and quickly reduced with the temperature 25-65℃.β-glucan had the remarkable effection on blood sugar and weight of normal rats and so did for blood sugar and blood lipid of STZ diabetes rats.β-glucan had the function to reduce weight, TC and LDL-C for diabetes rats, and increase HDL-C.β-glucan had the remarkable treatment against diabetes.In a word, the starch, oil andβ-glucan of oat had its unique properties which were used to selectively in food production. Oat oil had the powerful effect of hydroxyl radical scavenging and antioxidation, andβ-glucan of oat had the remarkable effect on blood sugar and blood lipid of rats.
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